The present invention relates to a video coding system for mail shipments. More particularly, the present invention relates to a coding system for mail shipments wherein the address field of an item of mail being conveyed along a conveyor path is scanned point-by-point by a scanner to produce a video signal without color information and this video signal is supplied to a video coding station wherein it is displayed on a monitor so that an operator can punch the distribution information associated with the displayed address into a keyboard.
In automatic mail distribution systems, the personnel working at the coding stations (coding personnel) have the task of detecting the addresses on successively presented mail shipments and punching into a keyboard the respectively associated distribution information, e.g., the information corresponding to the postal code or derived from the point of destination. This punched-in distribution information is then fed to a printer, located downstream in the conveying path, which provides each item with an identification imprint bearing the respective distribution information so as to then enable the items to be distributed by time and space autonomous machines.
In the conventional embodiment, the coding stations are included in a conveying system which includes incoming and outgoing conveying troughs, and they each comprise a stacking and separating device and a printer. The required multitude of conveying devices and other mechanical components not only brings about a certain susceptibility to malfunctions, but also leads to stresses on the coding personnel due to dust, noise and heat.
In the video coding system on which the present invention is based, the mechanical processes linked to the stream of conveyed items of mail and the processes derived from the contents of the address fields and associated with the plane of information processing are separated from one another in space and, to a certain respect, also in time. More particularly, in a video coding machine all items are brought in a continuous flow past a scanner which, by scanning the address field of the items in a point-by-point manner, produces a video signal containing the information from the address field. The video coding stations are disposed in another room from the conveyor and are equipped only with a monitor and a keyboard. The video signals associated with the individual letters are stored electronically in a suitable manner and distributed to the individual monitors. The keyed-in distribution information likewise is stored electronically in a suitable manner and associated with the individual letters, which reach the printer of the video coding machine via a mechanical storage path.
Such video coding systems are known, for example, from "ZPF" (Periodical for the Postal and Telegraph Services), 1974, pages 681-688 or from "Postpraxis" (Postal Practice), 1979, pages 197-203.
The introduction of the video coding technique undeniably constitutes a significant improvement in the operating conditions for the coding personnel. The display of the address field of the items of mail to be coded on the screen of a monitor, however, is also connected with certain physiological drawbacks. Inter alia, the monotone (signal color) of the background on the screen (e.g., black print on light green background) may cause the operator to additionally see the complementary colors and result in fatigue phenomena. An obvious measure to alleviate this would be to scan the items of mail and display the information in color using arrangements known from the color television art. However, this is not feasible from an economic point of view due to the large amount of equipment involved.